The Nurses Evaluation Rating Scale (NERS) consists of 16 items designed to capture salient dimensions of psychopathology and nursing care requirements for psychiatric patients. Reliability and validity of the NERS were evaluated by using a total of 3,052 sets of ratings accomplished by 19 staff nurses on a total of 235 adult psychiatric inpatients. All items of the NERS were utilized in describing psychopathology in this sample of patients, although no patient was positive on all items. Factor analysis revealed four distinct clusters of items, which represented higherâorder constructs of thinking disturbance, depression, anxiety, and psychomotor retardation. Testâretest reliability was found to be comparable to the reliability of most other clinical assessments of psychopathology. Scoring for the four factors was defined, and analysis of change during first 10 days of hospital stay revealed statistically significant improvement. The NERS appears to be a promising instrument for longitudinal, daily evaluations of inpatient psychopathology as seen in the routine clinical practice of psychiatric nurses.